Bioshock, one of the coolest games of the past few years, is finally spawning a sequel. And Gamespot got an exclusive look at the new edition of this bleak undersea shooter.

As in the original Bioshock, you'll be exploring the ruins of an undersea city that was supposed to be a utopia. This time around, it's ten years later, and you're a prototype "big daddy," escaping from mental conditioning by the mad scientist Dr. Bridgette Tenenbaum. Young girls are being kidnapped by a mysterious creature known as a "Big Sister," and Tenenbaum, the creator of the "Little Sisters," feels a sense of responsibility. It's hinted the "Big Sister" may be one of the "Little Sisters" freed at the end of the first game, who didn't take well to life on the outside. As you wake up at the start of the game, you hear Tenenbaum's voice urging you on to go find the Big Sister.

Here's a featurette about the new game:

And here are some awesome screenshots and concept drawings (more at the link below):

In the new game, you won't just explore Rapture, you'll be able to go outside as well, thanks to a fancy diving suit that comes with your "big daddy" armor. This'll provide a break from the non-stop claustrophobic action and also let you access a part of the city you couldn't reach otherwise. And you start to realize that Rapture and the sea-slug stem-cell substance ADAM are having on the local sea life, including weirdly mutated coral that's meshed with the city walls. You also get to visit the headquarters of Fontaine Futuristics. And as in the first game, you have a choice between saving Little Sisters, or harvesting ADAM from them. But you can also "adopt" them, which means they become your friends and help you find other sources of ADAM, which enhances your abilities. But if you adopt a Little Sister, you have to protect her from the vicious Slicers. And of course, the Big Sister is horrifying and totally lethal, with a needle arm and a cage on her back to hold Little Sisters.